With hugs and tears, southern Arizonans remembered the dead, the shattered lives and those who acted heroically after a gunman opened fire at an outdoor meet-and-greet that severely wounded Rep. Gabrielle Giffords and stunned the nation and this close-knit community.

The day of remembrance began with the ringing of church bells and hand-held bells throughout the city at 10:11 a.m., the exact time the gunman shot Giffords in the head and methodically moved down a line of people waiting to talk to her during a public event outside a Safeway supermarket on Jan. 8, 2011.

‘‘Even in the midst of this troubling year, the healing, the courage that we have experienced in our community — each one of us can notice how our cups overflow with the blessings of our lives,’’ said Stephanie Aaron, Giffords’ rabbi, who recited the 23rd Psalm at an interfaith service at the cathedral Sunday afternoon.

Relatives of the six dead walked solemnly down the aisle with a single red rose, placing the flowers in a vase in front of a picture of a heart.

Hundreds of people at the cathedral — including Gov. Jan Brewer — stood and chanted, ‘‘We remember, we remember, we remember with grateful hearts.’’ Some closed their eyes while others held each other.

Girls in white dresses and red sashes danced down the aisle as a song called ‘‘Hero in the Dark’’ played, and a pastor called on everyone to celebrate those who were lost and those who acted to save lives during the shooting.

Ron Barber, a Giffords staffer who survived two gunshot wounds, said he woke up Sunday dreaming about Giffords, who was severely wounded, and Giffords staffer Gabe Zimmerman, who died.

‘‘You have to think about the six people whose loved ones don’t have them today,’’ Barber said before the church service began.

At the Safeway memorial, Bruce Ellis and his wife Kelly Hardesty, both 50, held each other tight and wept as the bells rang.

‘‘It’s shocking to have a massacre like this occur in your backyard,’’ Ellis said. ‘‘It’s something that happens on the news, not in your neighborhood.’’

About 30 others rang bells, hugged each other and cried as the time of the shooting passed. Many bowed in prayer.

Giffords and her husband, former astronaut Mark Kelly, went to the scene of the shooting Saturday. They also visited University Medical Center, where Giffords was treated after the attack, and a trailhead outside Tucson named in honor of Zimmerman.

The couple was to join thousands at an evening candlelight vigil at the University of Arizona, with Kelly expected to speak. At an afternoon event at the University of Arizona, Colorado Sen. Mark Udall, who was born and raised in Tucson, spoke about Giffords.

He praised Giffords for working for the good of the country, and said other politicians can learn from her and move away from incendiary comments.

‘‘Although Gabby now struggles with her words at times, we know what she’s trying to say,’’ Udall said. ‘‘It’s a simply concept. Words matter, and these days you don’t hear our elected officials using words to bring us together. Too often words are used as weapons.’’

President Barack Obama called Giffords on Sunday to offer his support and tell her he and the first lady are keeping her, the families of those killed and the whole Tucson community in their thoughts and prayers, according to the White House. He said Giffords was an inspiration to all Americans.

Barber said he spent time with Giffords on Friday and Saturday.

‘‘Even though it’s a hard weekend for her and all of us, she wanted to be here with her community to remember,’’ he said. ‘‘She’s sad, we’re all sad, and she’s glad to be home.’’

Daniel Hernandez, Giffords’ former intern who came to her aid after the shooting and has been hailed as a hero, called Sunday a solemn day of remembrance and an opportunity to allow Tucson and those affected by the shooting heal further.

‘‘It’s definitely been a really difficult time for all of us,’’ he said. ‘‘But last time this year, there was a lot of anger. And now it’s, ‘How can we heal and move forward?’’’

Giffords, 41, has spent the last year in Houston undergoing intensive physical and speech therapy in a recovery that doctors and family have called miraculous. She is able to walk and talk, vote in Congress and gave a televised interview to ABC’s Diane Sawyer in May.

But doctors have said it would take many months to determine the lasting effects of her brain injury. The three-term congresswoman has four months to decide whether to seek re-election.

‘‘She’s making a lot of progress. She’s doing great,’’ said Rep. Debbie Wasserman Shultz, a close friend. ‘‘She still has a long way to go.’’

Jared Lee Loughner has pleaded not guilty to 49 charges in the shooting. The 23-year-old, who has been diagnosed with bipolar disorder, is being forcibly medicated at a Missouri prison facility in an effort to make him mentally ready for trial.

Many of the survivors have lobbied for gun legislation in Washington in hopes of preventing similar shootings and started various nonprofits that award scholarships, help needy children and promote awareness about mental illness.

Sunday’s events were designed to bring Tucson residents together the way they did a year ago.

On the night of the shootings, more than 100 people showed up outside Giffords’ office on a busy street corner in frigid temperatures, holding candles and signs that simply read ‘‘Peace’’ and ‘‘Just pray.’’ Strangers hugged, most cried and many sang anthems like ‘‘Amazing Grace.’’

In the days and weeks that followed, thousands of people contributed to makeshift memorials outside the office, the Tucson hospital where Giffords and other shooting victims were treated and the grocery store where it happened.

Others that came later included a 9-foot, 11-inch sculpture of an angel forged from World Trade Center steel in memory of Green.

At the Safeway, Gail Gardiner, 70, who lives about a mile away, tied a balloon Sunday that said, ‘‘Thinking of you,’’ to a railing next to a memorial of the shooting that reads: ‘‘The Tucson Tragedy ... we shall never forget.’’

‘‘This is my backyard and this is where I want to be and show people that we remember this,’’ Gardiner said. ‘‘It just hits so close to home and so many innocent people’s lives were taken and changed forever.’’

Albert Pesqueira, assistant fire chief for the Northwest Fire District in Tucson, was one of the first responders to the shooting. He came to the Safeway on Sunday to remember and to heal.

His most vivid memories from that day are the sounds of moaning and crying among shooting victims in the aftermath of the attack.

‘‘I can still hear them,’’ Pesqueira said. ‘‘We’ll never be the same. We’ll never be normal again because of what occurred.’’